In contemporary society with worldwide energy crisis and strong environmental protection consciousness, improvement of energy utilization efficiency and development of renewable energy sources, with no doubt, have become the two aspects of sustainable development energy. Besides, wind energy. which attracts more and more people' s attentions, has become one of the "green energies" with large scales and development and application prospects. Approximately 20% of solar radiation received by the earth can be transformed into wind energy and all energy consumption can be fulfilled if 1% of total amount of wind energy throughout the world can be used for power generation. Therefore, as the main form of wind energy utilization, wind power generation has been developed rapidly in the long run.

Under normal circumstances, the outlet voltage of wind power generating unit adopted by our country is 690V and long-distance power devilry can be realized through pressure boosting. In wind farms, cable is generally adopted to connect the wind driven generator to the wind power dedicated box-type booster substation; the power is delivered to the central substation of the wind farm when it is boosted to 40.5 (12) kV; after that, power is further boosted in the central substation and then be delivered to the power grid; unit wiring of "one transformer for one machine" is adopted for the combination of fan and box-type booster substation. The 40.5kV wind power dedicated box-type booster substation designed and manufactured by our company has been operated in network in wind farms of Inner Mongolia, northwest China, etc.